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AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil

Product code : DHDQT-EA

4.9 star rating Read 1,537 reviews

Customer Rating

4.9

92% would recommend

  • 5 1472
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,537 reviews
  • 5 star rating
    Good product
    By  MARK,  a  Verified Buyer  on  December 15, 2025
    Seems to be good
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Simply the best oil
    By  MICHAEL,  a  Verified Buyer  from  Québec Canada  on  December 12, 2025
    outstanding protection for all weather condition!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    WORKS AS PRESCRIBED
    By  PHILLIP,  a  Verified Buyer  from  Florida  on  December 12, 2025
    BEEN USING THIS FOR YEARS NOW IN MY 2015 SILVERADO 3500, I LOVE THE PRODUCT.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Exceptional
    By  TODD,  a  Verified Buyer  from  Florida   on  December 10, 2025
    My Powerstroke diesels run extremely well using Amsoil. First one had 242k on it and is still running great. My son still has it and my second one has 140k on it. Still going strong. Go 10-12k per oil change.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil signature series 15w 40 full synthetic oil
    By  BILLY,  a  Verified Buyer  from  Colcord Oklahoma   on  December 10, 2025
    I've been using the Amsoil sig. Series full synthetic 15 w 40 oil in my Duramax turbo diesel engine in 2 trucks I have owned, it is an excellent oil ,wouldn't use anything else ,I recommend this oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Simply the best
    By  RICKY,  a  Verified Buyer  from  San Diego  on  December 10, 2025
    This is the best oil out there
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    It works and works well
    By  ANTHONY,  a  Verified Buyer  from  Maine  on  December 07, 2025
    I consistently get oil analysis done on my engine, and since switching to this oil a few years ago I have noticed much better results. If you are in a pinch, it feels less guilty to go a little further as well - also verified by said analysis.
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  • 5 star rating
    The best oil on market
    By  EDWIN,  a  Verified Buyer  from  Miami  on  December 06, 2025
    Excellent product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  JOSH,  a  Verified Buyer  from  Edmond ok  on  December 05, 2025
    Love thus stuff only thing I use
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  • 5 star rating
    You get what you pay for.
    By  RICK,  a  Verified Buyer  from  Texas  on  November 30, 2025
    I’m a believer in the Amsoil product. I’ve been using it for years some people claim that it’s too expensive but when you spend all that money on a vehicle, a little extra on oil won’t hurt.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best yet
    By  BEN,  a  Verified Buyer  from  Wyoming  on  November 27, 2025
    Been running a readily available brand for years, rhymes with bell. Made the switch on my 2006 Dodge 5.9 Cummins the last service I did and there was an immediate difference. Engine is quieter, smoother, and I have noticed a slight increase in fuel economy. Have since bought Amsoil for my entire fleet (cost isnt that much more) and will be switching as soon as they need serviced. 100% recommend making the switch.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The Absolute Best Diesel Engine Oil
    By  DANNY,  a  Verified Buyer  from  Wyoming  on  November 23, 2025
    My 2013 Silverado 2500HD Duramax is a “Working Beast” I drive for a Crew of Amish Barn Builders, towing a 30’ Gooseneck trailer with 4 men beside myself. This Signature Series Oil makes my Duramax “ Growl” like a wild Beast. I was a “Purple” fan for decades- I won’t run any other engine oil since I first tried Amsoil Signature Series, at 155,000 miles- It’s still pulling Strong- Thanks Amsoil 👍
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 1 star rating
    Do better
    By  KEVIN,  a  Verified Buyer  from  Non ya business   on  November 22, 2025
    Stop offering cheap products for free with purchase. Do better
    Bottom Line
    No, I would not recommend this to a friend.
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  • 5 star rating
    Great Synthetic oil.
    By  STEVEN,  a  Verified Buyer  from  Billings MT  on  November 21, 2025
    Wouldn't buy any other synthetic oil in any of my vehicles.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Bottle seal issue
    By  WILLIAM,  a  Verified Buyer  from  Idaho   on  November 20, 2025
    I have use AMSOIL for years. For all my vehicles and equipment. I wish AMSOIL would develop an easy to remove bottle seal. Very hard to remove. Less expensive oil cap doesn't need this silver seal.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amazing Product
    By  BRAD,  a  Verified Buyer  from  USA  on  November 20, 2025
    I have a 2020 L5P. After using Amsoil on my last oil change the typewriter tick went away. I bought the kit online. Fast delivery on top of everything. Truck runs smooth and sounds great. Amazing product. Definitely buying again
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  Buddy,  a  Verified Buyer  on  November 19, 2025
    I use Amsoil lubes in all my vehicles
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 3 star rating
    Good oil, bad shipping.
    By  JOSH,  a  Verified Buyer  on  November 18, 2025
    I have run Max Duty 15w40 in my 12 valve Cummins for many years with excellent results under extreme conditions and been very pleased. The only problem has been getting it here. UPS (oops!) successfully destroys almost every box from Amsoil, and some have leaked. Maybe they should try FedEx. We have had much better results from them.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Simplement la meilleur huile
    By  MICHAEL,  a  Verified Buyer  from  Canada  on  November 16, 2025
    Je ne suis pas inquiète à propos de l'usure lorsque je pousse ma camionnette à ses limites!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good stuff
    By  MARTIN,  a  Verified Buyer  from  OHIO   on  November 11, 2025
    Good stuff
    Bottom Line
    Yes, I would recommend this to a friend.
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